Tensions have risen in the British province since councillors voted on December 3 to limit the number of days the Union Jack can fly over the City Hall to 17, outraging loyalists who believe Northern Ireland should retain strong links to Britain.

Loyalists have held protests, often violent, in several parts of Northern Ireland since the ruling.

Some 3500 people died in the three decades of violence between Northern Irish Protestants favouring continued union with Britain, and Catholics seeking a unified Ireland.

A 1998 peace agreement largely ended the conflict, but sporadic unrest and bomb threats continue as dissident offshoots remain violently opposed to the power-sharing government in Belfast, formed of Catholic and Protestant parties.